this is terrifying... (just in time for halloween)

The Arctic Ocean could be largely ice-free and open to shipping during the summer in as little as ten years' time, a top polar specialist has said.

"It's like man is taking the lid off the northern part of the planet," said Professor Peter Wadhams, from the University of Cambridge.

Professor Wadhams has been studying the Arctic ice since the 1960s.

He was speaking in central London at the launch of the findings of the Catlin Arctic Survey.

The expedition trekked across 435km of ice earlier this year.

Led by explorer Pen Hadow, the team's measurements found that the ice-floes were on average 1.8m thick - typical of so-called "first year" ice formed during the past winter and most vulnerable to melting.
The survey route - to the north of Canada - had been expected to cross areas of older "multi-year" ice which is thicker and more resilient.

When the ridges of ice between floes are included, the expedition found an average thickness of 4.8m.

Professor Wadhams said: "The Catlin Arctic Survey data supports the new consensus view - based on seasonal variation of ice extent and thickness, changes in temperatures, winds and especially ice composition - that the Arctic will be ice-free in summer within about 20 years, and that much of the decrease will be happening within 10 years.

"That means you'll be able to treat the Arctic as if it were essentially an open sea in the summer and have transport across the Arctic Ocean."

According to Professor Wadhams, faster shipping and easier access to oil and gas reserves were among short-term benefits of the melting.

But in the longer-term, losing a permanent feature of the planet risked accelerated warming, changing patterns of circulation in the oceans and atmosphere, and having unknown effects on ecosystems through the acidification of waters.

http://news.bbc.co.uk/2/hi/science/nature/8307272.stm